Shoe press pad



Jan. 10, 1939 L. E; BEST ETA| 2,143,101

SHOE PRESS PAD 4 Filed Jul 26,1955 2 Sheets-Sheet 1 konarcyg Wzlazd(3.0a m,

O ATTORNEY;

Jan. 10, 1939. E. BEST ET AL SHOE PRESS PAD Filed July 26, 1935 2Sheets-sheaf. 2

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Patented Jan. 10, 1939 UNITED STATES PATENT OFFICE SHOE PRESS PADporation of Delaware Application July 26, 1935, Serial No. 33,320

16 Claims.

This invention relates to inflatable pads adapted for use in shoepresses of the kind used for sole pressing operations such as cementoutsole afiixing, sole leveling, channel laying, and the like.

A primary object of the invention is to provide a shoe press pad capableof giving improved performance in the cement aifixation of soles tolasted uppers.

More particularly, objects of the invention are to provide a shoe presspad which is adapted firmly and fully to fit and press against the soleof a shoe and to impart accurately distributed sole amxing pressurethereto with a materially minimized consumption of air.

Another object of the invention is to provide a press capable of givingimproved performance, which at the same time is capable of ready andeconomical manufacture in quantity. i

A further object of the invention is to provid a method of making apress having the above and other herein described advantages.

Other objects of the invention will in part be obvious and will in partappear hereinafter.

The invention accordingly comprises the several steps and the relationof one or more of such steps with respect to each of the others, and thearticle possessing the features, properties, and the relation ofelements, which are exemplified in the following detailed disclosure,and the scope of the application of which will be indicated in theclaims,

For a fuller understanding of the nature and objects of the inventionreference should be had to the following detailed description taken inconnection with the accompanying drawings, in which:

Fig. l is a side elevation of a shoe press equipped with an inflatablepad embodying principles of the present invention, the lower partthereof being shown in section better to illustrate the padconstruction;

Fig. 2- is a perspective view of the inflatable pad view view

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it is customary to place an outsole against a lasted upper with cementtherebetween and to press these parts together in a shoe press having aninflatable or fluid filled pad in which the fluid pressure is increasedin order to urge the upper pad diaphragm against the sole of the shoe.Pressure may also be increased, using such pads, by mechanically orhydraulically forcing the shoe thereagainst. These presses also areuseful in other sole pressing operations, such as sole leveling andchannel laying.

Heretofore, a common form of pressure pad has comprised a soft rubberbladder which is generally enclosed in a leather casing and isinflatable in that it is adapted to have its interior pressure increasedin a suitable manner, such as by any of the above indicated methods. Inmost sole afi'ixing operations it has been customary, with such previouspads, to utilize an air pressure or its equivalent, of about 55 lbs. persquare inch or more. With these previously used leather cased pads, thequality of the work obtained has been found to improve as the padbecomes aged or broken in, continued use thereof forming a pliable orseasoned pocket in the area underlying the shoe which gradually becomesapproximately contoured to the general configuration of the bottoms ofshoes. This pocketed formation, in an old broken in pad, enables the paddiaphragm more closely to hug the shoe bottom, even at the relativelycurved parts such as the shank, and assures improved affixing results.

In accordance with the present invention, there is provided a pad which,even when new, gives sole affixing performance which is equivalent orsuperior to that obtained with an old broken in leather casing, and thisat an average pressure of around lbs. per square inch as compared withthe previous pressures indicated.

The present inventors have found that where the pressure is accuratelyapplied, the amount of pressure may be reduced. That is, if fullaccurate surface contact between the pad and shoe is provided, thenlower pressures are effective to produce the required affixing results.By permanently pocketing the pad to approximately the contours of shoebottoms, so that when even in an inert condition the pad tends to fitagainst the sole, less pressure is needed than when a non-fitting pad isforced into conformity with the shoe, and this decreased pressure, inthe case of the pad about to be particularly described, is equallyeffective with and even more effective than the higher pressures usedwith previous forms of pads. Further, the advantages of accurate surfacecontact between the pad and shoe are obtained, within the contemplationof this invention, by providing a sole contacting diaphragm of quiteflexible but relatively inextensible rubber, which is adapted readily toaccommodate itself to the contours of shoe bottoms, and at least some ofsuch benefits may be obtained with a diaphragm of this kind even when ithas no, or else a very slight, preformed pocketed contour,

The pad constructed in accordance with the present invention is moldedor otherwise suitably formed from rubber. it comprises an inflatablecasing which has no interior bladder but is itself formed with desiredareas of flexible elastic rubber, or rubber and fabric. Its flexibilityand extensibility are controlled so that these properties preferablyobtain in a greater degree in some areas of the pad than in others, allin accordance with the inflating characteristics that are desired.Further, in accordance with the best practice of thepresent invention,the shoe contacting upper diaphragm of the present molded rubber pad isinitially fitted to the general contour of the shoe bottoms with whichit is to be used, thus eliminating breaking in, while at the same timeproviding all the advantages obtaining with a broken in pocketedstructure. To this last end, the pad of the present invention ispreferably designed for use with right or left shoes only. Theillustrated pad shown in the present drawings is intended for use with aleft shoe, it being understood that a right shoe pad will have a similarbut in a sense reversed symmetrical structure. The upper surface of thepad, particularly at the shank and forepart portions, is conformed tothe lines of a broken in leather casing so that the desirable contourobtaining in such casing is uti lized at the outset. This can readily beaccomplished by making a plaster cast of such a broken in casing andforming a rubber mold therefrom. This cast is preferably furthermodified in order to idealize the contour of the ultimately molded orcast rubber pad, this modification comprising a suitable revision of thecast contour so as to produce a contour approximating thecharacteristics of those types of shoe bottoms which are to be operatedon. This revision, in the case of a molded rubber pad, comprisesdecreasing, to some extent, the severity of the curvatures obtaining inthe original model, so that the least curved among those shoes that areto be operated on may readily fit within the molded pocket of thefinished rubber pad. Also, the pad may be molded from a suitablearbitrarily designed pattern having these desired characteristics as tosize and contour. Thus, a given pad may preferably be made for operatingon left shoes in womens and misses styles, although it will beunderstood that the closeness of the conformity of the pad contour tothe shoe may be varied as desired, provided commensurate tolerance isgiven in the expansibility and conformability of the pad material, sothat advantages of the invention can be obtained even when widelydifferent types of shoes are operated on with the same press. In fact,it is contemplated that many of the advantages of the invention are tobe obtained by mak ing the pad pocket quite roughly approximate thebottoms of shoes, so that both right and left shoes in an extendedvariety of styles and sizes may be handled. Further, by providing a padhaving an upper diaphragm that is readily flexible, some of theadvantages as to accuracy of applied pressure are obtained withoutpocketing such diaphragm at all, or by only slightly accommodating thepad structure to the shoe contour. For example, an advantageous form ofrubber pressure pad is provided within the field of this invention byconstructing it substantially in accordance with the pocketed form asspecifically illustrated while permanently shaping its upper diaphragmto approximate only certain contours of shoe bottoms, as for exampletheir longitudinal contours. However, the greatest advantages are foundto accrue when a relatively close fit be tween the pad and shoe isprovided.

The pad constructed in accordance with this invention is adapted to beused in any suitable form of complementary press structure. Referringmore particularly to the drawings, a pad generally designated I3 isshown in a press H having integrally cast therewith a rigid bow memberI2 from which depends a toe post i3 and a heel post id. The heel posthas a fiat under surface l5 which is adapted to seat over the top of thecone of various lasts, and the entire post is preferably verticallyadjustable to a number of dilferent positions by means of any suitableadjusting device such as the cam 14'. tire press structure as hereinillustratively picted conforms to that shown in the applica .1 ofWilliam C. Card, Jr., Serial No. 677,899, June 2'7, 1935, and the heelpost adjustment may preferably be of the kind particularly shown in thatapplication.

The pad ID, as explained above, is formed of molded or cast rubber andits upper diaphragm comprises a forepart engaging portion i, a shankengaging portion l1, and a heel engaging portion I8. The forepart andshank portions are molded in general conformity to the bottoms of theshoes to be used thereover, in the present instance, say to the shankand forepart contour of a ladys leit shoe. The heel portion !8 ispreferably flat, as shown. Further, these various portions havedifferent degrees of extensibility and elasticity, the toe, ball andshank portions being relatively more extensible than the heel portion,as will hereinafter be more particularly explained.

In the pad illustrated, a combined air inlet and outlet conduit l9communicates with the interior of the pad through the bottom wallthereof, at

a point underlying the forepart of a shoe and V somewhat rearwardly ofthe toe portion thereof. The introduction of air through this conduittends to expand or dilate the pad, and serves to press its upperdiaphragm upwardly against the shoe bottom, as will be readilyunderstood.

The rubber, from which the pad is cast, par ticularly certain top areas,is so vulcanized as to be rather live or elastic, but the walls are madequite thick, being on the order of of an inch in thickness over most ofthe extent of the upper diaphragm so as to curtail or stiffen itsextensibility. This extensibility is further Controlled and limited byembodying in the pad diaphr gm a layer 20 of fabric. This fabric extendsover entire upper diaphragm and continues around to the under side ofthe pad, so as to be firmly anchored therein. If desired, the fabricinsert also may continue down the vertical sidewalls 35 of the pad inorder further to limit their extensibility, although this structure isnot specifically illustrated. The fabric is suiiiciently loose y wovenso as to have some extensibility, while still providing a limitingfactor against pronounced distension of the pad. The pad, thusconstructed,

is able to press up against the shoe sole in full pressing contact, butneed not unduly curl around the sides thereof so as to roll the soleedges. Its extensibility is what may be termed pronouncedly limited, ascompared, for example, with the highly distensible rubber padsfamiliarly known in foXing aflixing presses for tennis shoes.

The portion of the pad underlying the toe of the shoe, indicated at H,is preferably made relatively flexible and/or extensible as comparedwith certain other parts of the pad diaphragm in order to enable thediaphragm to bend up firmly against the toe of the shoe even thoughlasts having markedly diiferent toe lifts are used. In the presentillustrated construction this increased flexibility is obtained bymaking an air pocket 22 beneath the toe portion of the shoe and therebyseparating the pad diaphragm into a relatively thin, and hence moreflexible top ply 23 and an under ply 2d. The under ply Ed is permanentlyspaced from and of greater extent than the top ply 23, being curveddownwardly until it rests against the bottom wall 26 of the pad. Anopening affords constant communication between the air pocket 22 and thedepression 28 formed by a conduit receiving boss 29 in the bottom wallof the pad to which the con uit l is fitted as shown in Fig. 3. Theunder ply 2d of this toe air pocket merges rearwardly into the paddiaphragm at til, and from here rearwardly the central depressed orpocketed part of the diaphragm remains closely adjacent the bottom wallof the pad rearwardly approximately to the ball line at 35, andpreferably is seated thereon as indicated in Figs. 3 and 6 when the padis dellated. This air pocket structure at the toe also enables thevelocity head or pressure of the inrushing air initially to press thetoe of the shoe against the toe post it, so that the shoe is held firmlywhile the pressure against the entire sole gradually increases. It iscontemplated that this specific pocketed structure may be disposed with,if desired, but if this is done, suitable provision should be made forassuring requisite flexibility at this portion of the diaphragm.Satisfactory flexibility may be obtained by making such toe underlyingportion with substantially the same thickness and other characteristicsas the shank underlying portion, or, if preferred, either of suchportions may be relatively thinned with respect to the other in order toprovide any required flexibility. At the ball line, and rearwardlythereof throughout the shank portion, the shoe pocket of the pad slopeslaterally upward as shown at 32 and these respective slopes beingcontoured to t e under portion of the shoe so that in the case of a leftshoe pad the slope at 32 is generally somewhat more abrupt than that atThese upwardly sloping portions gradually flatten out at the sides ofthe pad as indicated at 3 1 (Fig. 6) and merge into sidewalls 35thereof.

Forwardly of the toe portion, the upper diaphragm rises sharply awayfrom the lower pad wall into the front end portion 36 of the pad whichis generally configured so as snugly to fit within the pocket of thepress casting as indicated at Fig. 1. An air space 3'! thus is providedfrom the toe part of the shoe forwardly to the front of the pad and theupper diaphragm is slightly convex forwardly of the toe portion as isindicated in Fig. 4.

The shank portion of the upper diaphragm also slopes upwardly away fromthe bottom pad wall providing air space at 38, and at the juncture ofthe rear of the shank portion and the front of the heel seat portion,indicated at 39, the upper diaphragm levels oil into the flattened heelportion l8.

Laterally of the heel portion it, the upper surface of the pad diaphragmis thinned out as shown at 43 (Figs. 2 and 7), and interiorly of the padthe adjacent wall structures are gradually thickened as shown at ii.This provides a relatively inflexible flat heel seat engaging por tionwhich is subject to elevation more or less as whole against the bottomof the heel seat of the shoe, through fi-exure of the thinned out wallsunderlying sections 433, these Walls being" thinnest in ie areasdesignated 52 (Fig. 7). Since the heel portion of the upper of acemented shoe is usually tackdasted, and likewise is relatively flat andstiff, it is not desirable or necessary to have a flexible diaphragmaction at this part of the shoe as is wanted at the more convex andirregularly configured shank and forepart portions. Instead, it isdesirable to protect the heel of the shoe against undue pressure, aswell as against rolling action of the pad, and to this end it has beencustomary in the past to insert rigid guard plates at this'portion ofthe shoe press, either within a pocket sewed to the pad casing or elseoverlying the same at or closely adjacent the heel seat portion.

In accordance with the structure of the present pad, the proper anddesired action at the heel is obtained by providing a heel section i8which is fiat and rather stiff and is adapted to be forced erticallyupward as a whole during the application of pressure to the pad. Also, arigid metallic plate it" may desirably be molded or embedded the heelsection is in order further to stiffen it, although this is notessential if such section is made of sufficiently thick and stillrubber. The extreme rearniost portion of the pad at ll-'3 is formed ofsolid rubber, thus further limiting the vertical movement of the heelportion to.

The entire pad may conveniently be molded in separate top and bottomsections joinable along a line dd, as shown in Fig. 1, although theinvention is not intended to be limited to this particula; form ofassembly.

In a typical sole afiixing operation, a lasted upper and an outsole areregistered with cement therebetween and placed in a press such as thatshown in Fig. l, the pad being deflated during this loading operation.Air is then introduced through the conduit i5, passing therefrom throughthe orifice 2? and under the toe underlying top ply lifting the latterclosely up against the toe portion of the shoe. The entire diaphragmalso is urged snugly up against the bottom of the shoe, and thediaphragm construction is such that the pressure first acts to cause itto hug closely up against the convex portions, parti ularly at theshank, and then to apply p essure over the whole sole after accuratecontact therewith has been established. By virtue of its moldedstructure the pad diaphragm already closely approximates that of theshoe bottom so that no undue amount of extension and repositioningthereof is required. The toe, ball and shank portions of the diaphragmare sufliciently flexible and extensible to assure their readyconformability to the shoe placed thereover, and the heel portion isvertically movable with these other portions so as to press upwardlyagainst the shoe heel. Because of the pad conformation and structure,the shoe does not tend to slide or tilt either longitudinally orlaterally.

Through use of a pad constructed in accordance with these principles, ithas, as pointed out above, been found possible to obtain sole affixingresults equal or superior to those obtained with previously used presseswhile using the relatively lower air pressures indicated. Further, theentire air cavity within the press is, through the present design, keptto a minimum volume commensurate with the desired diaphragm action, sothat the present pads characteristic economy as to air consumption isenhanced. This not only provides marked economies as to air consumption,but leads to easier and more convenient and rapid operation of thepress.

While inflation and deflation of the pad cavity through conduit l9 bymeans of compressed air is a desirable and suitable way of controllingthe pressure of the pad diaphragm, it is contemplated that any suitableform of fluid pressure may be exerted beneath the upper diaphragm, andthat the latter may be mounted on the press in any suitable manner forreceiving such pressure from beneath, or that the shoe may be pressedagainst the pad as above indicated.

It will be seen that there has been provided a shoe press padconstruction which possesses marked advantages, and which is well suitedto fulfil its intended purposes.

Since certain changes in carrying out the above method, and certainmodifications in the article which embody the invention may be madewithout departing from its scope, it is intended that all mattercontained in the above description or shown in the accompanying drawingsshall be interpreted as illustrative and not in a limiting sense.

It is also to be understood that the following claims are intended tocover all of the generic and specific features of the invention hereindescribed, and all statements of the scope of the invention which, as amatter of language, might be said to fall therebetween.

Having described our invention, what we claim as new and desire tosecure by Letters Patent is:

1. A shoe pressing device comprising a diaphragm made of rubberpermanently pocketed to approximate the contours of shoe bottoms saiddiaphragm being so constructed as to size and relative pliability and sosupported as to have readily flexible shank and forepart engagingportions and a comparatively stiff heel engaging portion, means forconfining fluid beneath said diaphragm, and means for increasing thepressure of the fluid against the diaphragm.

2. A shoe pressing device comprising a diaphragm made of elastic rubberhaving pronouncedly limited extensibility, which is permanently pocketedto approximate the contours of shoe bottoms, said diaphragm being freelyand naturally flexible at its shank and forepart engaging portions, andalso being of greater fullness at said portions than at the heelengaging portion, means supporting the edges of said diaphragm, meansfor confining fluid beneath said diaphragm, and means for increasing thepressure of the fluid against the diaphragm.

3. A shoe pressing device comprising a diaphragm made of elastic rubberof suflicient thickness pronouncedly to limit its extensibility, whichis permanently pocketed to approximate the contours of shoe bottoms,said diaphragm having freely flexible shank and forepart engagingportions and a relatively stiffer heel engaging portion, meanssupporting the edges of said diaphragm, said diaphragm having morefullness between its supported edges adjacent said relatively flexibleshank and forepart engaging portions than at the heel to provide greaterexpansibility at said relatively flexible portions, means for confiningfluid beneath said diaphragm, and means for increasing the pressure ofthe fluid against the diaphragm.

4. A shoe pressing device comprising a diaphragm made of elastic rubberhaving a fabric insert of limited extensibility embedded therein, saiddiaphragm being permanently pocketed to approximate the contours of shoebottoms said diaphragm being so constructed as to size and relativepliability as to have freely and naturally flexible curved shank andforepart portions and a comparatively flatter heel portion, saiddiaphragm being so supported at its edges as to have greater freedom towrap up against the shoe bottom at highly curved portions thereof thanat the flatter heel portion, means for confining fluid beneath saiddiaphragm, and means for increasing the pressure of the fluid againstthe diaphragm.

5. A shoe pressing device comprising a diaphragm made of elastic rubberhaving sufficient thickness to have pronouncedly limited extensibilityand. having freely flexible shank and forepart portions which are fullerand more flexible than the heel engaging portion, means supporting theedges of said diaphragm so as to provide greater freedom to wrap upagainst the shoe bottom at the fuller shank and forepart portions thanat the heel, means for confining fluid beneath said diaphragm, and meansfor increasing the pressure of the fluid against the diaphragm.

6. A shoe pressing device comprising a diaphragm made of elastic rubberwhich is freely and naturally flexible at its shank and forepartengaging portions and has less thickness and greater fullness at saidportions than at the heel engaging portion, means for confining fluidbeneath said diaphragm, and means for increasing the pressure of thefluid against the diaphragm.

7. A shoe pressing device comprising a diaphragm made of rubberpermanently shaped to approximate the contours of shoe bottoms andhaving portions of differing effective pliability located so as toprovide greatest flexibility at its toe engaging portion, leastflexibility at its heel contacting portion, and an intermediateflexibility between said portions, means for confining fluid beneathsaid diaphragm, and means for increasing the pressure of the fluidagainst the diaphragm.

8. A shoe pressing device comprising a rubber diaphragm having arelatively thick inextensible heel engaging portion supported laterallyby thinner portions, means for confining fluid beneath said diaphragm,and means for increasing the pressure of the fluid against thediaphragm.

9. A shoe press pad formed of rubber and having a pocketed upperdiaphragm permanently shaped to approximate the contours of shoebottoms, said diaphragm having its relatively curved forepart and shankengaging portions freely and naturally flexible and of greater fullnessthan the heel to provide greater vertical expansibility at saidrelatively curved portions, the heel portion being comparatively flatand of greater stiffness than said shank and forepart portions, said padhaving an interior cavity underlying said shank and forepart portionsthroughout their entire extent and adapted to contain a pressure fluid,and means controlling the pressure of such fluid.

10. A shoe press pad formed of elastic rubber and having an upperdiaphragm permanently pocketed to approximate the contours of shoebottoms, and having an interior cavity adapted to contain a pressurefluid underlying the curved shank and forepart portions of saiddiaphragm throughout their entire extent, the walls of said pad beingsufficiently thick to have pronouncedly limited extensibility, and soconstructed as to size and location as to provide greater verticalexpansibility at the shank and forepart engaging portions of saiddiaphragm than at the heel engaging portion.

11. A hollow, fluid containing shoe press pad formed of rubber having anupper diaphragm permanently pocketed to approximate the forepart andshank contours of shoes, and having a relatively flat heel underlyingportion extending rearwardly from said pocketed portion, the walls ofsaid pad being so constructed as to provide greater expansibility at thepocketed portion of the pad than at the heel.

12. A hollow, fluid containing shoe press pad formed of rubber having anupper diaphragm permanently pocketed to approximate the forepart andshank contours of shoes, and having a relatively flat heel underlyingportion extending rearwardly from said pocketed portion, the walls ofsaid pad being so constructed as to thickness and location as to providegreater expansibility at the pocketed portion of the pad than at theheel, the thickness of said walls being sufiicient pronouncedly to limittheir extensibility, and a fabric insert of limited extensibilityembedded in said diaphragm.

13. A hollow, fluid containing shoe press pad formed of rubber andhaving an upper diaphragm permanently pocketed to approximate thecontours of shoe bottoms, the toe underlying portion of said diaphragmbeing thinner than other shoe engaging portions thereof.

14. A hollow, fluid containing shoe press pad formed of rubber andhaving an upper diaphragm permanently pocketed to approximate thecontours of shoe bottoms, the toe underlying portion of said diaphragmbeing thinner than other shoe engaging portions thereof and the heelunderlying portion of said pad being less expansible than the forepartand shank engaging portions.

15. A hollow inflatable shoe press pad formed of rubber and having anupper diaphragm permanently pocketed to approximate the contours of shoebottoms, said diaphragm being of sufficient thickness pronouncedly tolimit its extensibility, the toe underlying portion of said diaphragmbeing separated to form an interior air pocket having a relatively thintop wall, the lower wall of said air pocket having a port communieatingwith the interior of the pad.

16. A hollow inflatable shoe press pad formed of rubber and having anupper diaphragm of sufficient thickness pronouncedly to limit itsextensibility, the toe underlying portion of said diaphragm beingseparated to form an interior air pocket having a relatively thin topwall, the lower wall of said air pocket having a port commimicating withthe interior of the pad.

WILLARD C. DURHAM. LEONARD E. BEST.

